Organosilicon compounds



United States Patent The portion of the term of the patent subsequent to July 6, 1982, has been disclaimed 21 Claims. (Cl. 260448.8)

This invention generally relates to organosilicon compounds and is particularly concerned with novel 1,2- siloxaalkanes and a process for the preparation of such compounds. 1 i

In recent years, organosilicon compounds have gained importance and recognition to an ever increasing extent. Of particular importance and interest are, in this connection, compounds which may be considered formed frompartly hypothetical-monomolecular organosilicon compounds wherein the Si atom has attached thereto at least one hydroxy-substituted alkyl group and at least one directly bonded hydroxyl group. Such polyfunctional silicon compounds are capable of forming by condensation cyclic compounds of the general formula 0 (I) or polymeric compounds of linear or cyclic structure corresponding to the formula [-SI i-M- O x In these formulas, M stands for a divalent substituted or unsubstituted hydrocarbon group, linking Si and 0 through at least 3 carbon atoms. Examples are: --(CH 2)4-, I

-cH oH,-c1an and CH;OHCI H:-

CH; (3H,

Several processes yielding such compounds have become knownin recent years. However, these prior art processes have several serious disadvantages and shortcomings. The primary reason that the prior art processes have not been generally accepted by the industry is that the starting materials for these processes are hydroxyalkyl-silicon compounds which are not readily available. Further, the hydroxyalkyl-silicon compounds which may successfully be utilized in the prior art processes are limited to those species wherein the residualfree valences of the silicon atom as indicated in the Formulas I and II above are exclusively saturated by or attached to alkyl or tr-ialkylsilyloxy groups which are slow to react and are no longer capable of cross linking.

Accordingly, it is a primary object of this invention to overcome the shortcomings of the prior art processes by providing a process wherein readily available starting substances are reacted in an exceedingly simple manner to yield 1,2-siloxaalkanes.

Another object of this invention is to provide a process for the preparation of 1,2-siloxaalkanes in high yields.

It is also an object'of this invention to provide novel 1,2-siloxaalkanes.

Another object of this invention is to provide 1,2- siloxaalkanes which have a wide utility and application for industrial use.

Generally it is an object of this invention to improve on the art of organosilicon compounds and processes for their preparation.

Briefly and in accordance with this invention, 1,2- silooxaalkanes are prepared by reacting, in the presence of a catalyst, an alkenoxy-group containing silane (A) with a silane (B) which latter has a hydrogen atom directly linked to the silicon atom and which comprises at least one halogenat-om or alkoxy group. The remaining valences at the silicon atoms of the silanes (A) and (B) are saturated by hydrocarbongroups. ".The reaction is carried out in the presence of a catalyst suitable for causing the addition of olefinically unsaturated compounds to Si.-H groups. Such catalysts are known per se. Hexachloroplatinum acid or platinum-activated carbon may be mentioned as examples for suitable catalysts.

According to a preferred embodiment, the reaction is carried out between a silane (A) of the general formula R,,Si(OCH -CH==CH and a silane (B) of the general formula p HSiR X In these formulas:

R stands for a substituted or unsubstituted hydrocarbon p;

X is a halogen atom or an alkoxy group;

a has a numerical value of between 0 and 3; and

b has a numerical value of between 0 and 2.

Preferred meanings for R and X are methyl and chlorine, respectively. However, although methyl is the preferred R group, it should be realized that any suitable hydrocarbon group as, for example, ethyl, butyl, isobutyl, amyl, halogenbutyl, benzyl or phenyl groups may he employed.

The reaction surprisingly takes the following course:

In the light of the state of the art, it should have been expected that the reaction product would correspond to a-compound of the formula asirot noa Rbxabu...

However, apparently such compounds are not sufficiently stable and continue to react to yield the products III and IV as indicated above.

Reaction product IV is obtained as a lay-product and may be removed from the reaction mixture. Such removal may be effected by distillation. In case X of Formula II described above is chlorine, it may be advantageous to efiect the distillation under simultaneous passing through of HCl or under addition of pyridine. In case X is an alkoxy radical it may be advantageous to effect the distillation under addition of an alkaline catalyst, e.g. an alkalialcoholate. Upon separation of the reaction by-prod'uct IV from the main reaction product, reaction by-product IV may again be used as starting material for the preparation of the alkenoxysilane of Formula A.

The reaction is accelerated by increasing the temperature. Thus, experiments have established that the reaction is carried out with excellent yields at temperatures above 50" C. and preferably between and C. The reaction is often advantageously carried out in a pressure vessel or autoclave, particularly it higher temperatures are employed, since the silane of Formula IY generally exhibits a relatively low boiling point.

According to a modification of the inventive process, the silane groups necessary for carrying out the inventive reaction may be provided in a single molecule. In other words, a compound may be used which contains groups corresponding both to the silane (A) and the silane (B).

According to this modification of the inventive procedure, a silane is employed which contains an Si-H group and at least one alkenoxy group, while the valences remaining at the silicon atom may be saturated by hydrocarbon, alkoxy or halogen groups. This silane is then heated in the presence of a catalyst of the previously indicated nature, i.e. a catalyst which is suitable for causing addition of unsaturated compounds to SiH groups.

Such silanes which contain both the groups of the silanes (A) and (B) may correspond to the formula wherein R stands for a hydrocarbon group and/or an allyloxy group and/ or alkoxy or chlorine, and mixtures of these groups.

The reaction with compounds which combine the groups of the silane (A) and the groups of the silane (B) in one single molecule may proceed analogous to the abovedescribed reaction course in intermolecular or intramolecular manner.

Thus, the reaction may proceed intramolecularly as follows:

H (CH2):

This reaction may simply be carried out by dropping the starting compound together with the catalyst into a heated vessel.

The 1,2-siloxaalkanes prepared in accordance with the process of this invention may be obtained in cyclic monomeric, in cyclic or linear polymeric form. The polymeric siloxaalkanes are usually depolymerized by heat to form the monomeric compounds. Upon distilling the siloxaalkanes, the monomeric or dimeric compound is usually first found in the distillate. This monomeric or dirneric compound is capable of again polymerizing at room temperature. However, if the distillate is maintained at low temperatures, for example if it is deposited on a cool surface, then polymerization is inhibited and the compound will remain in its monomeric or dimeric form. If the polymers are dissolved in a solvent, an equilibrium is established between the polymers with its monomers or dimers, respectively.

The inventive compounds have a wide variety of uses. Thus, for example, they are exceptionally suitable for modifying silicon resins. Further, they react with isocyanates or synthetic resins such as alkyd resins. The inventive compounds can also be incorporated in other organosilicons. This may be accomplished in a simple manner by using known equilibration catalysts.

The invention will now be described by several examples, it being understood, however, that these examples are given by way of illustration and not by way of limitation and that many changes in the choice of raw materials and process conditions in general may be effected without affecting in any way the scope and spirit of the invention as recited in the appended claims.

EXAMPLE I C. 115 grams (1 mole) of methyldichlorosilane are dropped into the reaction mixture within the course of one hour. The reaction mixtures is continuously agitated during the addition of the methyldichlorosilane. Agitation is continued for an additional ten hours. During this period, the temperature of the reaction mixture rises to about C. A further amount of 0.3 ml. of H PtCl solution is then added and the reaction mixture is thereafter stirred for an additional six hours at a temperature of about 85 C. The reaction product is distilled through a column. The first fraction which distills up to the boiling point of about C. consists essentially of trimethylchlorosilane. The bath temperature is thereafter increased to about 250 to 300 C. A product distills over whose boiling temperature, dependent on the bath temperature, fluctuates to a certain extent, but is within the temperature range of about to 200 C. The major portion of the distilled product solidifies in the receiving vessel to form large crystals. The yield is 98 grams, which corresponds to 72% of the theoretical amount calculated on 1-methyl1-chloro-1,2- siloxacyclopentane.

Analysis-Actual amount: Si, 20.4; C, 34.6; H, 7.0; Cl, 25.85. Theoretical amount: Si, 20.5; C, 35.15; H, 6.58; Cl, 26.0.

The distillate which solidifies in crystalline form consists probably of the dimeric product 1,6-dimethyl-1,6- dichloro-1,2,-6,7 -disiloxacyclodecane. These crystals, upon standing, polymerize to form a viscous liquid.

EXAMPLE II A mixture consisting of 82 grams (0.5 mole) of triethoxysilane, 65 grams (0.5 mole) of trimethylallyloxysilane and 0.5 gram of carbon activated with 2% of Pt are stirred in an autoclave for six hours and at a temperature of C. The platinum catalyst is thereafter removed by filtration and the reaction mixture is subjected to fractional distillation. The first fraction obtained at a temperature of between 72 and 93 C. weighed 45 grams and consisted mainly of trimethylethoxysilane. The second fractionof 13 grams is obtained in the temperature range of 93 to C. Thereafter, at bath temperatures of between 290 and 350 C., 86 grams of 1,l-diethoxy-l,2-silox'acyclopentane distill in a boiling range of 180 to 230 C., particularly 220 to 225 C. 86 grams of the compound obtained corresponds to 75% of the theoretical amount.

Analysis.Actual amount: Si, 16.2; C, 46.9; H, 9.6; ethoxy, 52.1. Theoretical amount: Si, 15.9; C, 47.7; H, 9.1; ethoxy, 51.1.

The liquid thus obtained is mobile and polymerizes upon standing to a highly viscous mass.

EXAMPLE III 135.5 grams (1 mole) of silicochloroform are added in the course of one hour to a mixture of 130 grams (1 mole) of trimethylallyloxysilane, 0.5 gram of triethylenediamine'and 0.05 gram of H PtCl -6H O. The bath temperature was about 70 C. The reaction mixture was then heated for an additional ten hours to a temperature of 70 C. The mixture was agitated during the heating. The reaction mixture partially formed a gel. The volatile components of the reaction mixture were then expelled in awater jet vacuum by heating to about 60 C. These volatile components were condensed in a cooled receiver. The distillate consisted of 105 grams of trimethylchlorosilane, the theoretical amount being 108.6 grams. The residue consisted of 345 grams of a gel-like substance. This substance constitutes substantially pure polymeric 1,1-dich1oro-1,2-siloxacyclopentane. The theoretical amount would be 361 grams. 7

Analysis-Actual amount: Si, 18.2; C, 23.2; H, 41; Cl, 44.0. Theoretical amount:- Si,-17.9;-C, 22.9 H, 3.8; Cl, 45.1.

EXAMPLE IV 1 -chlor0-1 -phenyl-1 ,2-siloxacyclapemane According to Example I, 130 grams (1 mole) of trimethylallyloxysilane are reacted with 177 grams (1 mole) of phenyldichlorosilane at a temperature of 100 C. The resulting trimethylchlorosilane is removed by distillation. The substance remaining behind consists mainly of polymeric l-chloro-1-phenyl-1,2-siloxacyclopentane.

Analysis-Actual amount: Si, 13.5 %;C, 55.1%; H, 5.3%; Cl, 17.2%. Theoretical amount: Si, 14.11%; C, 54.40%; H, 5.54%; Cl, 17.89%.

EXAMPLE V 1-chlor0-1-mezfhyl-1,2-sil0gcacycl0hexane According to Example I, 144 grams (1 mole) of t-rimethyl-(2-buten-4-oxy)-silane are reacted with 155 grams (1 mole) of methyldichlorosilane and the reaction product is subjected to fractional distillation. The fraction obtained at a temperature of between 135 and 145 C. consists mainly of l-chloro-l-methyl-1,2-siloxacyclohexane.

Yield 105 grams, which corresponds to 70% of the theory.

Analysis.Actual amount: Cl, 22.9%. amount: CI, 23.6%.

EXAMPLE VI 1 -chloro-1,4-dimethyl-1,2-sil0xacyclopentane According to Example I, 144 grams (1 mole) of trimethylmethallyloxysilane and 115 grams (1 mole) of methyldichlorosilane are reacted and distilled.

Yield 99 grams,-which corresponds to 66% of the theory; Boiling range 150-220 C.

Analysis.-Actual amount: Si, 18.3%; C, 39.6%; H, 7.1%; Cl, 23.2%. Theoretical amount: Si, 18.60%; C, 39.87%; H, 7.31%; Cl, 23.60%.

EXAMPLE VII 1 -chl0r0-1 -methyl-1,2-siloxacyclopentane According to Example I two tests are made, whereby 86 grams (0.5 mole) of dimethyldiallyloxysilane are reacted with 115 grams (1 mole) of methyldichlorosilane. The reactant product is subjected to fractional distillationat first through a column (a) by passing through a moderate flow of HCl-gas and (b) by adding grams of pyridine, whereby nearly the entire dirnethyldichlorosilane expected is obtained. The residue is distilled without a column, whereby there are obtained (a) 92 grams of l-chloro-l-methyl-l,2-siloxacyc1opentane, which corresponds to 67% of the theory, and (b) 98 grams of 1- chloro-l-methyl-1,2-siloxacyclopentane, which correspond to 72% of the theory. Both these products are identical with the one obtained according to Example I.

EXAMPLE VIII 1 -chlor0-1 -methyl-1,2-sil0xacycl0pen tane (a) Methylallyl0xychlorosilane.-1 16 grams (2 moles) of allylalcohol are dropped into 230 grams (2 moles) of methyldichlorosilane whilst being cooled and stirred, whereafter the cooler is removed and the reaction product heated at 40 C. within the course of one hour and is then distilled through a column.

BPqeo 99-103 C., yield 164 grams, which corresponds to 60% of the theory.

(b) 1 -chlor0-1-methyl-1,2 siloxacyclopentane.-Whilst being stirred 136.5 grams (1 mole) of methylallyloxychlorosilane are dropped into a three-neck flash containing 0.3 ccm. of a 0.12 molar ethanolic solution of and being in an oil bath of 120 C. At first the dropwise addition must be eifected very slowly; later on it is carried out thus that the temperature of the reaction mixture,

Theoretical which on account of the exothermic reaction rises very quickly, does not exceed C. Within 25 minutes all methylallyloxychlorosilane is dropped in. The reaction mixture is then further heated to 140 C. within the course of half an hour. According to the IR-spectrum the product is in the main identical with the one obtained according to Example I.

Analysis.Actual amount: CI, 25.5%. amount: Cl, 26.0%.

While specific embodiments of the invention have been described in detail to illustrate the application of the principles of this invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

, 1. Organosilicon compounds of the formula Theoretical R is selected from the group consisting of alkyl, aryl and halogen R is halogen, and M stands for alkylene, linking Si and 0 through 3-4 carbon atoms.

2. A compound as claimed in claim 1, wherein R is methyl and R is chlorine. i

3. A compound as claimed in claim 1, wherein R is ethyl and R is chlorine.

4. A compound as claimed in claim 1, phenyl and R is chlorine.

5. A compound as claimed in claim 1, chlorine and R is chlorine.

6. l-chloro-1methyl-1,2-siloxacyclohexane.

7. A process of preparing 1,2-siloxaalkanes, which comprises reacting an alkenoxy-group containing silane (A), said alkenoxy being selected from the group consisting of propene(1)oxy and butene(l)oxy, with a silane (B), said silane (B) having a hydrogen atom directly bonded to Si at least one of the remaining valences of Si being satisfied by a member selected from the group consisting of halogen and alkoxy, the remaining valences of said silanes (A) and (B) being substituted by aliphatically saturated hydrocarbon groups, said reaction being carried out in the presence of a catalyst capable of causing addition of olefinically unsaturated compounds to SiH groups.

8. A process as claimed in claim 7, wherein said catalyst'is selected from the group consisting of hexachloro platinum acid and carbon activated with platinum.

9. A process as claimed in claim 7, wherein said reaction is carried out at a temperature of about between 50 to C.

10. A process of preparing 1.1-si1oxaalkanes which comprises reacting a silane (A) of the general formula R,,Si(OCH P--CH=CH with a silane (B) of the general formula HSiR X wherein R is wherein R is 13. A process as claimed in claim 10, wherein said silanes (A) and ('B) are reacted according to the formula III IV and wherein the reaction Product IV is removed by distillation.

14. A process as claimed in claim 13, wherein X=Cl and the removal of said reaction Product IV is facilitated by passing hydrochloric acid through the reaction mixture.

15. A process of preparing 1,2-si-loxaalkanes which comprises heating a si lane containing an Si-I-I group and at least one alkenoxy group selected from the group consisting of propene(1)oxy and butene(l)oxy, the residual valences of the Si atom of the silane being satisfied by members selected from the group consisting of aliphatically saturated hydrocarbon groups, alkoXy, allyloxy halogen and mixtures thereof, said heating being effected in the presence of a catalyst capable of causing addition of unsaturated compounds to Si-H groups.

16. A process as claimed in claim 15, wherein said silane corresponds to the formula halogen, and mixtures thereof.

17. A process as claimed in claim 13, wherein X=Cl and the removal of said reaction. Product IV is facilitated by adding pyridine to the reaction mixture.

18. Compounds of the unit formula 20. Polymers of the unit formula ('11 CuH Si--CHzCH2CH2GHzCHh 21,. Compounds of the unit formula (31' CH3 CHs-Sfi-CHaOHzCHOHnCI-I References Cited by the Examiner UNITED STATES PATENTS 2,486,162 10/1949 Hyde 260448.2 2,711,417 6/ 1955 Frisch 260-448.8 2,906,735 10/ 1959 Speier 260448.2 2,967,171 l/1961 Barnes et al. 260-448.8 2,983,744 5/1961 Knoth 260-448.8 2,983,745 5/1961 Speier 260448.8

TOBIAS E. LEVOW, Primary Examiner.

SAMUEL H. BLECH, Examiner.

P. F. SHAVER, Assistant Examiner. 

1. ORGANOSILICON COMPOUNDS OF THE FORMULA
 10. A PROCESS OF PREPARING 1.1-SILOXAALKANES WHICH COMPRISES REACTING A SILANE (A) OF THE GENERAL FORMULA 